Wales, Ireland - and potentially England - could all be in the title mix in next weekend's final round of Six Nations action, but Irish hopes of a first tournament clean sweep since 2009 ended following a 23-16 defeat.

Substitute centre Scott Williams' second-half try proved the difference in comfortably the best game of this season's championship, while full-back Leigh Halfpenny kicked five penalties and fly-half Dan Biggar dropped a goal.

Ireland responded with a 69th-minute penalty try, plus 11 points from fly-half Johnny Sexton's boot, but they suffered a first defeat in 11 Tests and only their third since coach Joe Schmidt took charge almost two years ago.